The Research Of Corrosive And Repair On Reinforced Concrete Chimney After Wet Flue Gas Desulfurization In Power Plan

Flue gases emissions from coal-fired power plant contain amounts of SO2and othercorrosive gases. Wet flue gas desulfurization process were widely used in the domesticindustry of thermal power desulfurization process. As the temperature of the smokeafter wet desulfurization （FGD） were lower than the acid dew point，whether theinstallation of gas-gas heating system （GGH） or not，the sulfuric acid vapor form bywater vapor and flue gas will condense down，resulting in low-temperature corrosion ofconcrete chimney.The invasion of corrosive condensate will trigger the concretereinforcement corrosion，greatly shorten the service life of concrete structures，and mayalso cause the structural corrosion damage in short term.Core samples at different heights on the chimney to study the ion erosion paths ofvarious corrosive environmental conditions. Through field and laboratory experimentsmeasuring the corrosion potential of the specimen、CaCO₃content、carbonation depth、SO^4-content、Cl^-content、NO^3-ion content、porosity、the outer wall of the chimneyrebound value and compressive strength to analysis the corrosion factor of the chimney.The results shows that: the compressive strength and the core samples testingconcrete strength to meet the design requirements, high density，reinforced protectivelayer thickness meet the requirements，and the lower outer chimney almost no corrosionactivity，also slight carbonation of the chimney wall，the severe carbonation of foulingand lower platform；the high degree density of concrete；the enough protective layerthickness of reinforced；the serious intrusion of chloride ion. The corrosion damage ofmonocular chimney were more serious, and the durability was poor.The paper hascomprehensive analysis the durability of monocular chimney and evaluation of seismicdisasters，and combined with the current construction technology，refer to thetechnologies and their implementation feasibility，to consider the chimney corrosionresearch. The results may also provide certain reference to the practical engineering.